I fear my fancy idea ruined our friendship for good

I'M 25 and need some advice on a close friendship, which I’m worried I've messed up for good.

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I've been friends with this girl since we were in year nine. She was part of my friend group, but I was always attracted to her. All the boys were. At school, I never thought I had a chance with her, so never asked her out and was happy to stay friends.

Over the years, though, as we've grown up, we've become closer and I'd say she was one of my best mates. My problem is, a couple of weeks ago we went out together and for some mad reason, I admitted to her that I'd always fancied her and would love it if we were to be more than friends.